As a result of rapid societal development and change, and the development of processed food, a variety of instant and processed food is being produced and distributed. In addition, more and more convenience stores are increasingly available where consumers can get the convenience food. In particular, high school students who are under great stress from the pressures of academic learning in order to prepare for university, tend to be attracted to convenience food as it is easily accessible and suits their taste preferences. The imbalance of nutrition for this youth group is very concerning. This study aims to identify the status of high school students with respect to their consumption of convenience food purchased from convenience stores, in order to evaluate their dietary habits and their nutrition quotient.
The mean age of the subjects in the study was 16.70 years old. With respect to the frequency of convenience store usage, our subjects were divided into 3 groups; the first group consists of 141 students who use convenience stores less than 1 time a week (29.7%); the second group consists of 191 students who use convenience stores 1-2 times a week (40.3%); and the third group who use convenience stores more than 3 times a week (24.0%). Besides their frequency of convenience store usage, there was no significant difference among the occupational status three groups, which includes their grades, whether or not their mothers, the number of family members their after-school private activities, or hours of watching/using TV or electronic devices (p<0.001). In terms of the gender dispersion of the three groups, male students appeared more than females in the group who use convenience stores more often, i.e. 43.20% of male students use convenience stores less than 1 time a week, 41.88% of male students use convenience stores 1-2 times a week, and 63.16% of male students use 3 times or more a week. In terms of the allowance dispersion among the three groups, students with more allowance appeared to use convenience stores more frequently, i.e. 55.03% of students in the group using convenience stores less than 1 time a week had an allowance amount of 50,000 KRW or less, 46.07% of students in the group that use convenience stores 1-2 times a week had an allowance amount of 50,000 KRW or less, and 48.25% of students in the group that uses convenience stores 3 times or more a week have an allowance in the amount of 50,000-100,000 KRW (p<0.001).
With respect to awareness of the frequency of using convenience stores, students with more frequent usage appeared to be more aware of their frequency (p<0.001). Students who use convenience stores more frequently appeared to use them 3-4 a week (p<0.001). The most utilized time slot for using convenience stores to purchase instant foods was during the afternoon snack break or late at night. In response to a question regarding the reason for using instant foods at convenience stores, most students in all three groups cited convenience as the main reason, followed by taste, and then reasonable prices. On the other hand, with respect to concerns of purchasing and consuming instant food from convenience stores, 29.59% of the students in the group that uses convenience stores less than 1 time a week and 27.19% of the students in the group that uses the stores 3 times or more a week indicate that the unsanitary conditions of the stores was the greatest concern, while 34.55% of the students in the group that uses convenience stores 1-2 times a week appear to be concerned about the lack of nutrition in the food the most.
With regards to the time spent for food consumption of the three groups, the group of students that use convenience stores most frequently appeared to spend the shortest time for consuming their meals (p<0.05). Although there seemed to be no difference between the frequency of having breakfast for the three groups and the difference in frequency of using convenience stores, all of the groups appear to have breakfast every day at the higest ratio. Students that use convenience stores more frequently consumed late-night snacks or street-vendor food more often (p<0.001 each). Among the three groups, no significant difference was showen for consuming vegetables, fruit, white milk, or fish; however, students that use convenience stores more frequently consumed ramen, sugary and oily bread, or drinks more often (p<0.001 each).
With respect to NQ-A, which evaluates the nutrition quotient for Korean adolescents according to the frequency of the subjects using convenience stores in this study, the scores was 55.71 for the group that uses convenience stores less than 1 time a week, 52.26 for the group that uses 1-2 times a week, and 49.97 for the group that uses 3 times or more a week, which showed that the group that uses convenience stores the most frequently had the lowest score compared to the other two groups (p<0.001). When it comed to each category of evaluation, the group that uses 3 times or more appears to have a lower score than the other two groups in the categories of ''Moderate'' (p<0.001) and ''Environment'' (p<0.05) whereas there seems to be no difference between the three groups in the ''Balance'', ''Diversity'', or ''Practice'' categories.
From these results, approximately 70% or more of the high school students in this study used convenience stores more than 1 time a week. The amount of allowance seemed to significantly affect the frequency of convenience store usage, i.e. students who used convenience stores more often appeared to have more allowance. In addition, students who use convenience stores more frequently tended to spend a short time for consuming food and have convenience food, sugary and oily snacks, or drinks, as well as late-night snacks or street-vendor food more often. With respect to the nutrition evaluation of food quality according to the nutrition quotient for Korean adolescents, the results show that the students who used convenience stores the most frequently had lower scores for overall food quality and ''Moderate'', as well as ''Environment''. As such, it is suggested that the frequency of convenience store usage by high school students correlates with undesired dietary habits. Nevertheless, students tend to consume instant food from convenience stores because of their convenience, taste, or reasonable pricing, etc. In conclusion, it is suggested that an adequate guideline for desired dietary habits must be provided to students.